The present invention relates to a fiber structure which serves to intercept or shut out radiation in the infrared region by reflection, interference, etc. to provide coolness. The present invention also relates to cloths using the fiber structure and textile goods using such cloths.
As is well known, the spectrum of sunlight arriving on the earth""s surface has a wide extent ranging from the ultraviolet region to the infrared region. Comparison of the distribution of energy of sunlight by wavelengths reveals that the ultraviolet region with wavelength between 0.29 and 0.40 xcexcm corresponds to 6%, the visible region with wavelength between 0.40 and 0.78 xcexcm corresponds to about 52%, and the infrared region with wavelength of 0.78 xcexcm or more corresponds to about 42%.
It is thus understood that sunlight contains a unnegligible amount of infrared rays or energy. Infrared rays are also called xe2x80x9cheat raysxe2x80x9d since they are easily absorbed by objects to produce heat vibration of molecules, resulting in a temperature rise of the objects.
Conventionally, there is, in various fields, an increasing demand for development of products which can intercept or shut out infrared rays to avoid thermal influence by exposure thereto. By way of example, in the field of the textile industry, in order to avoid summer heat, development of everyday clothes is waited which can intercept infrared rays in sunlight to restrain a rise in skin temperature, providing coolness to human bodies. Moreover, in the field of the construction industry, window glasses, curtains, etc. are developed which can shut out infrared rays in sunlight to restrain a rise in room temperature due to sunlight entering through windows.
Infrared rays result from not only the sun, but various artificial heat sources such as a blast furnace and a boiler, which are heated at several hundred to several thousand xc2x0C. Thus, in the field of the manufacturing industry, in view of severe work environments where the above heat sources are in operation, development of working clothes, etc. is waited which can shut out infrared rays resultant therefrom to reduce severeness of working conditions for operators.
In view of development of textile goods such as clothes and curtains which can intercept or shut out infrared rays, it is desirable that material fibers and cloths made by weaving the fibers serve essentially to intercept infrared rays. Conventionally, such fibers are obtained, e.g. by coating or laminating one side of unprocessed fibers with films of titanic or chromic oxide or metal such as gold or nickel having higher reflectivity through deposition or sputtering. With those fibers, reflection of infrared rays is not carried out by the fibers themselves, but by the films coated or laminated.
However, such known fibers having infrared-rays reflecting films coated or laminated and containing oxide or metal not only lack feeling and drapeability, but have a drawback in view of durability due to easy breakaway of the films by mechanical friction produced by washing, etc.
It is, therefore, an object of the present invention to provide a fiber structure which serves to efficiently intercept or shut out radiation in the infrared region, with excellent durability and easy manufacture and without any infrared-rays reflecting film coated or laminated.
Another object of the present invention is to provide cloths using the fiber structure and textile goods using such cloths.
One aspect of the present invention lies in providing a fiber structure with a cross section having x-axis and y-axis directions, comprising:
an alternate lamination including:
a first portion having a refractive index na and a thickness da; and
a second portion adjacent to said first portion, said second portion having a refractive index nb and a thickness db,
wherein when 1.0xe2x89xa6na less than 1.8, 1.3xe2x89xa6nbxe2x89xa61.8, and 1.01xe2x89xa6nb/naxe2x89xa61.80, a primary peak wavelength xcex1 which is equal to 2(nada+nbdb) is given by xcex1xe2x89xa70.78 (xcexcm).
Another aspect of the present invention lies in providing a fiber structure with a cross section having x-axis and y-axis directions, comprising:
an alternate lamination including:
a first portion having a refractive index na and a thickness da; and
a second portion adjacent to said first portion, said second portion having a refractive index nb and a thickness db,
wherein when 1.0xe2x89xa6na less than 1.8, 1.3xe2x89xa6nbxe2x89xa61.8, and 1.01xe2x89xa6nb/naxe2x89xa61.80, a primary peak wavelength xcex1 which is equal to 2(nada+nbdb) is given by xcex1xe2x89xa71.6 (xcexcm).
Still another aspect of the present invention lies in providing a cloth, comprising:
a fiber structure with a cross section having x-axis and y-axis directions, said fiber structure comprising:
an alternate lamination including:
a first portion having a refractive index na and a thickness da; and
a second portion adjacent to said first portion, said second portion having a refractive index nb and a thickness db,
wherein when 1.0xe2x89xa6na less than 1.8, 1.3xe2x89xa6nbxe2x89xa61.8, and 1.01xe2x89xa6nb/naxe2x89xa61.80, a primary peak wavelength xcex1 which is equal to 2(nada+nbdb) is given by xcex1xe2x89xa70.78 (xcexcm).
A further aspect of the present invention lies in providing a textile product, comprising:
a cloth including a fiber structure with a cross section having x-axis and y-axis directions, said fiber structure comprising:
an alternate lamination including:
a first portion having a refractive index na and a thickness da; and
a second portion adjacent to said first portion, said second portion having a refractive index nb and a thickness db,
wherein when 1.0xe2x89xa6na less than 1.8, 1.3xe2x89xa6nbxe2x89xa61.8, and 1.01xe2x89xa6nb/naxe2x89xa61.80, a primary peak wavelength xcex1 which is equal to 2(nada+nbdb) is given by xcex1xe2x89xa70.78 (xcexcm).